tests: removing incorrect testcases of poll

These two test cases both are fault injection test cases,
and there are designed for testing some negative branches
to improve code coverage. But I find that this branch
shouldn't be tested, because the spinlock will be locked
before a procedure performs here, and then it will trigger
an assert error and the process will be rescheduled to the
handler function, and terminated the current test case,
so spinlock will never be unlocked. And it will impact
the next test case in the same test suite(the next testcase
will be never get spinlock).

Signed-off-by: NingX Zhao <ningx.zhao@intel.com>
(cherry picked from commit cb4a629b)